engleski

Dynamics of a boiler with natural water circulation

Republic of Croatia has inherent obligations to decrease its CO2 emissions in accordance with the Kyoto protocol and participation in the European Emissions Trading Scheme (EETS), which may impose notable additional running costs to heavy industries. These restrictive measures should therefore motivate the aforementioned industries (such as oil industry) to adopt low- emission technologies and optimize the production process in order to minimize the production-related emissions. As a basis for the production process emissions minimization, an appropriate detailed model of the production plant needs to be built. To this end, this paper presents the results of modeling of a natural water circulation boiler with one steam generation drum operating in a industrial power plant. The model accounts for all of key static and dynamic disturbance effects which may affect the safe and reliable plant operation. The behavior of the boiler media (water and steam) is modeled based on fundamental physical laws, thus resulting in a comprehensive nonlinear dynamic boiler model. The resulting model can be used to simulate any conceivable boiler operating regime because it does not contain any additional restrictions or operating regime-specific empirical relationships. In order to illustrate the effectiveness of the proposed model, boiler responses to typical disturbances have been analyzed for a wide range of operating regimes, including the case of water level control, which has shown rather good agreement with experimental data. The proposed model can be easily extended/modified for the purpose of dynamics analysis for boiler systems utilizing alternative fuels (bio-fuels), which may be characterized by notably different disturbance response speed, thus enabling optimization of the dedicated control system design.

natural circulation boiler ; nonlinear dynamic model ; physical modeling ; on-line monitoring ; process disturbance analysis

nije evidentirano